C1 Electronic Structure of Atoms

Electronic Structure Learning Objectives Key words Know how the electronic structure relates to the elements’ groups (5) To be able to represent the electron arrangement for elements 1-20 in 2 different ways (6) Understand and explain why an element’s group determines how it reacts (7) electrons, configuration, energy levels, negatively charged, valance electrons Starter Complete the exam-style questions sheet in front of you

Information you should already know Protons have a positive charge and electrons have a negative charge. Atoms are neutral because they have the same number of electrons as protons.  The protons are in the nucleus and do not change or vary except in some nuclear reactions. The electrons are in discrete pathways or shells around the nucleus.

Think! Does anyone know what the electronic structure of an atom looks like?

Electronic Structure Shell/ orbital/ energy level electrons nucleus Watch Electronic Structure Shell/ orbital/ energy level electrons nucleus Electronic Structure

Knowledge- must learn! When drawing (or writing) electronic configuration, you are only allowed 2 electrons on the first shell, 8 on the 2nd and 8 on the third. Any leftover are on the 4th.

Electronic Structure Helium atom (He) P protons P=2 E electrons Shell/ orbital/ energy level P protons E electrons N Neutrons electrons P=2 E=2 N=2 nucleus

Electronic Structure P=3 E=3 N=4 Lithium atom (Li) How many electrons does Lithium have?? P=3 E=3 N=4

Electronic Structure P=5 E=5 N=6 Boron (B) How many electrons does Boron have?? P=5 E=5 N=6

Electronic Structure P=11 E=11 N=12 Sodium (Na) How many electrons does Sodium have?? P=11 E=11 N=12 Notice there’s now 3 shells, as there's 11 electrons

Electronic Structure P=19 E=19 N=20 Potassium (K) How many electrons does Potassium have?? P=19 E=19 N=20 Notice there’s now 4 shells, as there's 19 electrons

Complete the worksheet Draw on the correct amount of electrons for each atom stated. DO NOT use the periodic tables ; see if you can see a pattern with an atom’s group compared with the electrons..!! LEAVE BLANK the electronic structure under the diagram blank for now

Writing the electronic structure On your worksheets there is a box that says ‘Electronic structure’. There, we write the electronic structure of that atom. How do we do it?? It’s really simple: Take fluorine as an example It has 2 electrons on its first shell, then 7 on its second. Therefore it has the configuration 2.7 If you understand, complete the electronic config for all the atoms on your worksheet. IF not, I will go through this again, slower

Linking points (Grade 6-7) Did anyone spot link between the number of valance electrons (electrons in the most outer shell) and the atom’s group?? Well, there is! The amount of valance electrons in an atom determines its group number Eg…. Fluorine has 9 electrons, therefore its electronic structure is 2.7 The last number (valance electron number) tell us the group that atom is in So we know, from this, that fluorine is in Group 7 – the halogens

In your books Complete the electronic structure – both drawing and writing – for the following elements: Carbon Sodium Fluorine Magnesium Argon HELP? Use your periodic tables that are in your plastic wallets

Task answers

Carbon Shell1 has 2 electrons Shell2 has 4 electrons 2.4

Sodium Shell1 has 2 electrons Shell2 has 8 electrons Shell3 has 1 electron 2.8.1

Fluorine Shell1 has 2 electrons Shell2 has 7 electrons 2.7

Magnesium Shell1 has 2 electrons Shell2 has 8 electrons Shell3 has 2 electrons 2.8.2

Argon Shell1 has 2 electrons Shell2 has 8 electrons Shell3 has 8 electrons 2.8.8

Video Clip Watch this 5 min clip on electronic structure https://www.youtube.com/watch?v=hSkJzE2Vz_w

Get ready for a 6-question quiz! Answer in books 1 What is another name for an electron shell? 2 How many electrons can go in the first electron shell? 3 How many electrons can go in the second electron shell? 4 How many electrons can go in the third electron shell? 5 What are the most outer electrons called? 6 What two subatomic particles is the atomic number equal to?

Answers Swap and peer assess Q1 orbitals / energy levels Q2 2 Q3 8 Q4 valance electrons Q6 protons and electrons

Worksheet Complete the double- sided questions sheet ‘Atomic Basics’ If you need another copy of the worksheet, it is available here: http://sciencespot.net/Media/AtomicBasics.pdf - the first two pages are for students, pgs 3-4 are answers http://sciencespot.net/Media/AtomicBasics.pdf

Homework – write in planners Subject – Science Details - Draw & write the electronic structure for Potassium (K), Lithium (Li), Calcium (Ca), Neon (Ne) and Sulphur (S) Due in – next lesson Complete on paper, I want your books in to mark NO excuses

Plenary Complete the questions sheet Only first page If you need another copy of the worksheet, it is available here: http://wbs.eu.com/download.php?url=/var/joomla/west-bridgford/httpdocs/phocadownload/Science/Y10_Unit_1_Revision/C1_revision/c1.1.1%20c1.1.2%20atoms%20and%20the%20periodic%20table%20q.pdf - the first page is the correct sheet